Object of the month

August 2023

Caerphilly Castle

This month sees the 100th anniversary of the introduction of the GWR’s famous Castle Class locomotives.  In celebration of this Object of the Month takes a look at one of the most iconic locomotives of the class, No. 4073 Caerphilly Castle, which is on display at STEAM.

Caerphilly Castle on display at STEAM.

Caerphilly Castle was the first of its class to roll off the production line at Swindon Works on 23rd August 1923.  In total 171 Castle Class engines were built, including rebuilds, between 1932 and 1950.  The Castle locomotives were designed by Chief Mechanical Engineer C. B. Collett who based them on the earlier Star Class engines but made them larger and more powerful.  They became the GWR’s most successful express passenger locomotive, operating on all of the GWR’s main lines.

Caerphilly Castle as it was when it came out of Swindon Works in August 1923.

Caerphilly Castle was displayed at the British Empire Exhibition in 1924, showcasing GWR engineering.  A notice accompanying the locomotive stated it to be the “Most powerful express passenger locomotive in Britain”.  The LNER who were displaying the Flying Scotsman locomotive at the exhibition disputed this, so trials were arranged between the two classes of engines.  The GWR proved its claim when the Castles won the trials in terms of coal and water consumption and speed.

Excerpt from British Empire Exhibition booklet, 1924.

For passengers the Castle locomotives, and in particular Caerphilly Castle, were amongst the GWR’s most exciting class to travel behind and a range of publicity material including a jigsaw, postcards, cigarette cards and books featured Caerphilly Castle.

One of the books for boys published by the GWR featuring Caerphilly Castle.

After running for almost 2 million miles Caerphilly Castle was withdrawn from service in 1960 and went into preservation as part of the National Collection.

This photograph taken at Paddington Station shows the handing over of the locomotive to the Science Museum at South Kensington in 1961

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